"In a parallel dimension, a nuclear holocaust caused by corrupt world leaders, seeking to rid the planet of the mutated beings they inadvertently created, has forced the human race to retreat underground... The effects of a biological weapon has caused some people to mutate, violent and blood thirsty, The Fallen; now ravage the land. Five once normal men, now reborn from the earth as disfigured but powerful warriors, have risen against The Fallen. They vow to take back the world of TERRA and destroy the mutant masses. They are Terraborn."